>Cheryl's tuning letter fall 2015 described a case where they implemented MSU capping ... [snip]
Ooops, I just saw the some text vanished from my mail... sorry for the incpmpleted data.. I wanted to add that the CPU Activity Report shows the system (LPAR) being busy between ~30% and ~50% (physically), and the whole CEC is nowhere near running at the physical (12CP ) capacity limits. We're running with Group Capacity Limit, and are also nowhere near being capped. So there should be enough spare capacity for the system (LPAR) to to use. But it does not. The 7 vertical low CPs are mostly parked or unparked for only a few percent. I wonder why MVS is not using more CPs and more Capacity for that job. But then there is the interesting comment from Greg: RMF might be fooling me. I understood RMF to count a CP delay sample when it finds a ready work unit on the WUQ (dispatcher queue). My (probably incorrect) thinking is that a ready WU should get access to a CP in this situation (spare capacity / parked CPs). This is why I'm interested in the mechanism that influence WU queueing and selection when HiperDispatch is on, i.e. when there is one WUQ per processor node. -- Peter Hunkeler ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
